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Mecanismo del asma inducida por el polen de hierba
C Suphioglu1, M B Singh, P Taylor
1School of Botany, University of Melbourne, Parkville, Victoria, Australia.
Lancet (London, England)
|March 7, 1992
Resumen
Las lluvias rompen el polen de la hierba de centeno, liberando pequeños gránulos de almidón que desencadenan el asma. Estos gránulos microscópicos, que contienen el alergeno Lol pIX, son lo suficientemente pequeños como para entrar en las vías respiratorias y causar constricción bronquial en individuos sensibles.
Área de la Ciencia:
- Investigación de los alérgenos.
- Salud ambiental Salud ambiental es la salud del medio ambiente.
- Medicina para las vías respiratorias.
Sus antecedentes:
- El asma a menudo está relacionado con la sensibilidad al polen de la hierba de centeno.
- Los granos de polen son demasiado grandes para llegar a las vías respiratorias inferiores, lo que plantea una pregunta sobre los mecanismos del asma.
Objetivo del estudio:
- Para investigar el mecanismo del asma inducida por el polen de la hierba de centeno.
- Para identificar cómo los alérgenos se liberan y llegan a las vías respiratorias inferiores.
Principales métodos:
- Pruebas in vitro de ruptura de polen por choque osmótico en agua de lluvia.
- Análisis de muestras atmosféricas para la concentración de gránulos de almidón.
- Pruebas de respuesta in vivo mediadas por IgE y pruebas de desafío bronquial en pacientes asmáticos.
Principales resultados:
- Los granos de polen de la hierba de centeno se rompen en el agua de lluvia, liberando numerosos pequeños gránulos de almidón (portadores de alérgenos Lol pIX).
- Las concentraciones de gránulos de almidón atmosférico aumentaron 50 veces después de las lluvias.
- Los gránulos aislados indujeron respuestas de IgE y constricción bronquial significativa en pacientes asmáticos.
Conclusiones:
- Los gránulos de almidón liberados del polen de la hierba de centeno son un mecanismo probable para desencadenar el asma.
- Estos pequeños gránulos pueden penetrar en las vías respiratorias y provocar respuestas alérgicas.
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